Skinner considered free will an illusion and human action dependent on consequences of previous actions. If the consequences are bad, there is a high chance the action will not be repeated; if the consequences are good, the probability of the action being repeated become stronger.[7] Skinner called this the principle of reinforcement.[8]

To strengthen behavior, Skinner used operant conditioning, and he considered the rate of response to be the most effective measure of response strength. To study operant conditioning, he invented the operant conditioning chamber, also known as the Skinner Box,[9] and to measure rate he invented the cumulative recorder. Using these tools, he and C. B. Ferster produced his most influential experimental work, which appeared in their book Schedules of Reinforcement (1957).[10][11]

The gravestone of B.F. Skinner and his wife Eve at Mount Auburn Cemetery

Skinner was born in Susquehanna, Pennsylvania, to Grace and William Skinner. His father was a lawyer. He became an atheist after a Christian teacher tried to assuage his fear of the hell that his grandmother described.[18] His brother Edward, two and a half years younger, died at age sixteen of a cerebral hemorrhage.

Skinner’s closest friend as a young boy was Raphael Miller, whom he called Doc because his father was a doctor. Doc and Skinner became friends due to their parents’ religiousness and both had an interest in contraptions and gadgets. They had set up a telegraph line between their houses to send messages to each other, although they had to call each other on the telephone due to the confusing messages sent back and forth. During one summer, Doc and Skinner started an elderberry business to gather berries and sell them door to door. They had found out that when they picked the ripe berries, the unripe ones came off the branches too, so they built a device that was able to separate them. The device was a bent piece of metal to form a trough. They would pour water down the trough into a bucket, and the ripe berries would sink into the bucket and the unripe ones would be pushed over the edge to be thrown away.[19]

He attended Hamilton College in New York with the intention of becoming a writer. He found himself at a social disadvantage at Hamilton College because of his intellectual attitude.[20] While attending, he joined Lambda Chi Alpha fraternity. Hamilton was known for being a strong fraternity college. Skinner had thought that his fraternity brothers were respectful and did not haze or mistreat the newcomers, instead, they helped out the other boys with courses or other activities. Freshman were called “‘slimers’” who had to wear small green knit hats and greet everyone that they passed for punishment. The year before Skinner entered Hamilton, there was a hazing accident that caused the death of a student. The freshman was asleep in his bed when he was pushed onto the floor, where he smashed his head, and resulting in his death. Skinner had a similar incident where two freshmen captured him and tied him to a pole, where he should have stayed all night, but he had a razor blade in his shoe for emergency and managed to cut himself free.[21] He wrote for the school paper, but, as an atheist, he was critical of the traditional mores of his college. After receiving his Bachelor of Arts in English literature in 1926, he attended Harvard University, where he would later research, teach, and eventually become a prestigious board member. While he was at Harvard, a fellow student, Fred Keller, convinced Skinner that he could make an experimental science from the study of behavior. This led Skinner to invent his prototype for the Skinner Box and to join Keller in the creation of other tools for small experiments.[20] After graduation, he unsuccessfully tried to write a great novel while he lived with his parents, a period that he later called the Dark Years.[20] He became disillusioned with his literary skills despite encouragement from the renowned poet Robert Frost, concluding that he had little world experience and no strong personal perspective from which to write. His encounter with John B. Watson's Behaviorism led him into graduate study in psychology and to the development of his own version of behaviorism.[22]

Skinner received a PhD from Harvard in 1931, and remained there as a researcher until 1936. He then taught at the University of Minnesota at Minneapolis and later at Indiana University, where he was chair of the psychology department from 1946–1947, before returning to Harvard as a tenured professor in 1948. He remained at Harvard for the rest of his life. In 1973, Skinner was one of the signers of the Humanist Manifesto II.[23]

Skinner’s public exposure had increased in the 1970s, he remained active even after his retirement in 1974, until his death. In 1989, Skinner was diagnosed with leukemia and died on August 18, 1990 in Cambridge, Massachusetts. Ten days before his death, he was given the lifetime achievement award by the American Psychological Association and gave a talk in an auditorium concerning his work.[28]

A controversial figure, Skinner has been depicted in many different ways. He has been widely revered for bringing a much-needed scientific approach to the study of human behavior; he has also been vilified for attempting to apply findings based largely on animal experiments to human behavior in real-life settings.

Skinner called his approach to the study of behavior radical behaviorism.[29] This philosophy of behavioral science assumes that behavior is a consequence of environmental histories of reinforcement (see Applied behavior analysis). In contrast to the approach of cognitive science, behaviorism does not accept private events such as thinking, perceptions, and unobservable emotions as causes of an organism's behavior. However, in contrast to methodological behaviorism, Skinner's radical behaviorism did accept thoughts, emotions, and other "private events" as responses subject to the same rules as overt behavior. In his words:

The position can be stated as follows: what is felt or introspectively observed is not some nonphysical world of consciousness, mind, or mental life but the observer's own body. This does not mean, as I shall show later, that introspection is a kind of psychological research, nor does it mean (and this is the heart of the argument) that what are felt or introspectively observed are the causes of the behavior. An organism behaves as it does because of its current structure, but most of this is out of reach of introspection. At the moment we must content ourselves, as the methodological behaviorist insists, with a person's genetic and environment histories. What are introspectively observed are certain collateral products of those histories.
...

In this way we repair the major damage wrought by mentalism. When what a person does [is] attributed to what is going on inside him, investigation is brought to an end. Why explain the explanation? For twenty five hundred years people have been preoccupied with feelings and mental life, but only recently has any interest been shown in a more precise analysis of the role of the environment. Ignorance of that role led in the first place to mental fictions, and it has been perpetuated by the explanatory practices to which they gave rise.[30]

Skinner's behavioral theory was largely set forth in his first book, Behavior of Organisms.[31] Here he gave a systematic description of the manner in which environmental variables control behavior. He distinguished two sorts of behavior—respondent and operant—which are controlled in different ways. Respondent behaviors are elicited by stimuli, and may be modified through respondent conditioning, which is often called "Pavlovian conditioning" or "classical conditioning", in which a neutral stimulus is paired with an eliciting stimulus. Operant behaviors, in contrast, are "emitted", meaning that initially they are not induced by any particular stimulus. They are strengthened through operant conditioning, sometimes called "instrumental conditioning", in which the occurrence of a response yields a reinforcer. Respondent behaviors might be measured by their latency or strength, operant behaviors by their rate. Both of these sorts of behavior had already been studied experimentally, for example, respondents by Pavlov,[32] and operants by Thorndike.[33] Skinner's account differed in some ways from earlier ones,[34] and was one of the first accounts to bring them under one roof.

The idea that behavior is strengthened or weakened by its consequences raises several questions. Among the most important are these: (1) Operant responses are strengthened by reinforcement, but where do they come from in the first place? (2) Once it is in the organism's repertoire, how is a response directed or controlled? (3) How can very complex and seemingly novel behaviors be explained?[clarification needed]

Skinner's answer to the first question was very much like Darwin's answer to the question of the origin of a "new" bodily structure, namely, variation and selection. Similarly, the behavior of an individual varies from moment to moment; a variation that is followed by reinforcement is strengthened and becomes prominent in that individual's behavioral repertoire. "Shaping" was Skinner's term for the gradual modification of behavior by the reinforcement of desired variations. As discussed later in this article, Skinner believed that "superstitious" behavior can arise when a response[clarification needed] happens to be followed by reinforcement to which it is actually unrelated.

The second question, "how is operant behavior controlled?" arises because, to begin with, the behavior is "emitted" without reference to any particular stimulus. Skinner answered this question by saying that a stimulus comes to control an operant if it is present when the response is reinforced and absent when it is not. For example, if lever-pressing only brings food when a light is on, a rat, or a child, will learn to press the lever only when the light is on. Skinner summarized this relationship by saying that a discriminative stimulus (e.g. light) sets the occasion for the reinforcement (food) of the operant (lever-press). This three-term contingency (stimulus-response-reinforcer) is one of Skinner's most important concepts, and sets his theory apart from theories that use only pair-wise associations.[34]

Most behavior of humans cannot easily be described in terms of individual responses reinforced one by one, and Skinner devoted a great deal of effort to the problem of behavioral complexity. Some complex behavior can be seen as a sequence of relatively simple responses, and here Skinner invoked the idea of "chaining." Chaining is based on the fact, experimentally demonstrated, that a discriminative stimulus not only sets the occasion for subsequent behavior, but it can also reinforce a behavior that precedes it. That is, a discriminative stimulus is also a "conditioned reinforcer." For example, the light that sets the occasion for lever pressing may also be used to reinforce "turning around" in the presence of a noise. This results in the sequence "noise - turn-around - light - press lever - food." Much longer chains can be built by adding more stimuli and responses.

However, Skinner recognized that a great deal of behavior, especially human behavior, cannot be accounted for by gradual shaping or the construction of response sequences.[35] Complex behavior often appears suddenly in its final form, as when a person first finds his way to the elevator by following instructions given at the front desk. To account for such behavior, Skinner introduced the concept of rule-governed behavior. First, relatively simple behaviors come under the control of verbal stimuli: the child learns to "jump", "open the book", and so on. After a large number of responses come under such verbal control, a sequence of verbal stimuli can evoke an almost unlimited variety of complex responses.[35]

Reinforcement, a key concept of behaviorism, is the primary process that shapes and controls behavior, and occurs in two ways, "positive" and "negative." In The Behavior of Organisms (1938), Skinner defined "negative reinforcement" to be synonymous with punishment, that is, the presentation of an aversive stimulus. Subsequently, in Science and Human Behavior (1953), Skinner redefined negative reinforcement. In what has now become the standard set of definitions, positive reinforcement is the strengthening of behavior by the occurrence of some event (e.g., praise after some behavior is performed), whereas negative reinforcement is the strengthening of behavior by the removal or avoidance of some aversive event (e.g., opening and raising an umbrella over your head on a rainy day is reinforced by the cessation of rain falling on you).

Both types of reinforcement strengthen behavior, or increase the probability of a behavior reoccurring; the difference is in whether the reinforcing event is something applied (positive reinforcement) or something removed or avoided (negative reinforcement). Punishment is the application of an aversive stimulus/event (positive punishment or punishment by contingent stimulation) or the removal of a desirable stimulus (negative punishment or punishment by contingent withdrawal). Though punishment is often used to suppress behavior, Skinner argued that this suppression is temporary and has a number of other, often unwanted, consequences.[36] Extinction is the absence of a rewarding stimulus, which weakens behavior.

Writing in 1981, Skinner pointed out that Darwinian natural selection is, like reinforced behavior, "selection by consequences." Though, as he said, natural selection has now "made its case", he regretted that essentially the same process, "reinforcement", was less widely accepted as underlying human behavior.[37]

Skinner recognized that behavior is typically reinforced more than once, and, together with C. B. Ferster, he did an extensive analysis of the various ways in which reinforcements could be arranged over time, which he called "schedules of reinforcement."[38]

The most notable schedules of reinforcement studied by Skinner were continuous, interval (fixed or variable), and ratio (fixed or variable). All are methods used in operant conditioning.

Continuous reinforcement (CRF) — each time a specific action is performed the subject receives a reinforcement. This method is effective when teaching a new behavior because it quickly establishes an association between the target behavior and the reinforcer.[39]

Interval Schedules — based on the time intervals between reinforcements[40]

Fixed Interval Schedule (FI): A procedure in which reinforcements are presented at fixed time periods, provided that the appropriate response is made. This schedule yields a response rate that is low just after reinforcement and becomes rapid just before the next reinforcement is scheduled.

Variable Interval Schedule (VI): A procedure in which behavior is reinforced after random time durations following the last reinforcement. This schedule yields steady responding at a rate that varies with the average frequency of reinforcement.

Ratio Schedules — based on the ratio of responses to reinforcements[40]

Fixed Ratio Schedule (FR): A procedure in which reinforcement is delivered after a specific number of responses have been made.

Variable Ratio Schedule (VR): A procedure in which reinforcement comes after a number of responses that is randomized from one reinforcement to the next (ex. slot machines). The lower the number of responses required, the higher the response rate tends to be. Ratio schedules tend to produce very rapid responding, often with breaks of no responding just after reinforcement if a large number of responses is required for reinforcement.[41]

An operant conditioning chamber (also known as a Skinner Box) is a laboratory apparatus used in the experimental analysis of animal behavior. It was invented by Skinner while he was a graduate student at Harvard University. As used by Skinner, the box had a lever (for rats), or a disk in one wall (for pigeons). A press on this "manipulandum" could deliver food to the animal through an opening in the wall, and responses reinforced in this way increased in frequency. By controlling this reinforcement together with discriminative stimuli such as lights and tones, or punishments such as electric shocks, experimenters have used the operant box to study a wide variety of topics, including schedules of reinforcement, discriminative control, delayed response ("memory"), punishment, and so on. By channeling research in these directions, the operant conditioning chamber has had a huge influence on course of research in animal learning and its applications. It enabled great progress on problems that could be studied by measuring the rate, probability, or force of a simple, repeatable response. However, it discouraged the study of behavioral processes not easily conceptualized in such terms—spatial learning, in particular, which is now studied in quite different ways, for example, by the use of the water maze.[34]

The cumulative recorder makes a pen-and-ink record of simple repeated responses. Skinner designed it for use with the Operant chamber as a convenient way to record and view the rate of responses such as a lever press or a key peck. In this device, a sheet of paper gradually unrolls over a cylinder. Each response steps a small pen across the paper, starting at one edge; when the pen reaches the other edge, it quickly resets to the initial side. The slope of the resulting ink line graphically displays the rate of the response; for example, rapid responses yield a steeply sloping line on the paper, slow responding yields a line of low slope. The cumulative recorder was a key tool used by Skinner in his analysis of behavior, and it was very widely adopted by other experimenters, gradually falling out of use with the advent of the laboratory computer.[citation needed] Skinner's major experimental exploration of response rates, presented in his book with C. B. Ferster, Schedules of Reinforcement, is full of cumulative records produced by this device.[38]

The air crib is an easily cleaned, temperature- and humidity-controlled enclosure intended to replace the standard infant crib.[42] Skinner invented the device to help his wife cope with the day-to-day tasks of child rearing. It was designed to make early childcare simpler (by reducing laundry, diaper rash, cradle cap, etc.), while allowing the baby to be more mobile and comfortable, and less prone to cry. Reportedly it had some success in these goals.[43]

The air crib was a controversial invention. It was popularly mischaracterized as a cruel pen, and it was often compared to Skinner's operant conditioning chamber, commonly called the "Skinner Box." This association with laboratory animal experimentation discouraged its commercial success, though several companies attempted production.[43][44]

The teaching machine was a mechanical device whose purpose was to administer a curriculum of programmed learning. The machine embodies key elements of Skinner’s theory of learning and had important implications for education in general and classroom instruction in particular.[47]

In one incarnation, the machine was a box that housed a list of questions that could be viewed one at a time through a small window. (See picture). There was also a mechanism through which the learner could respond to each question. Upon delivering a correct answer, the learner would be rewarded.[48]

Skinner advocated the use of teaching machines for a broad range of students (e.g., preschool aged to adult) and instructional purposes (e.g., reading and music). For example, one machine that he envisioned could teach rhythm. He wrote:

A relatively simple device supplies the necessary contingencies. The student taps a rhythmic pattern in unison with the device. "Unison" is specified very loosely at first (the student can be a little early or late at each tap) but the specifications are slowly sharpened. The process is repeated for various speeds and patterns. In another arrangement, the student echoes rhythmic patterns sounded by the machine, though not in unison, and again the specifications for an accurate reproduction are progressively sharpened. Rhythmic patterns can also be brought under the control of a printed score.[49]

The instructional potential of the teaching machine stemmed from several factors: it provided automatic, immediate and regular reinforcement without the use of aversive control; the material presented was coherent, yet varied and novel; the pace of learning could be adjusted to suit the individual. As a result, students were interested, attentive, and learned efficiently by producing the desired behavior, "learning by doing."[50]

Teaching machines, though perhaps rudimentary, were not rigid instruments of instruction. They could be adjusted and improved based upon the students' performance. For example, if a student made many incorrect responses, the machine could be reprogrammed to provide less advanced prompts or questions—the idea being that students acquire behaviors most efficiently if they make few errors. Multiple-choice formats were not well-suited for teaching machines because they tended to increase student mistakes, and the contingencies of reinforcement were relatively uncontrolled.

Not only useful in teaching explicit skills, machines could also promote the development of a repertoire of behaviors that Skinner called self-management. Effective self-management means attending to stimuli appropriate to a task, avoiding distractions, reducing the opportunity of reward for competing behaviors, and so on. For example, machines encourage students to pay attention before receiving a reward. Skinner contrasted this with the common classroom practice of initially capturing students’ attention (e.g., with a lively video) and delivering a reward (e.g., entertainment) before the students have actually performed any relevant behavior. This practice fails to reinforce correct behavior and actually counters the development of self-management.

Skinner pioneered the use of teaching machines in the classroom, especially at the primary level. Today computers run software that performs similar teaching tasks, and there has been a resurgence of interest in the topic related to the development of adaptive learning systems.[51]

During World War II, the US Navy required a weapon effective against surface ships, such as the German Bismarck class battleships. Although missile and TV technology existed, the size of the primitive guidance systems available rendered automatic guidance impractical. To solve this problem, Skinner initiated Project Pigeon,[52][53] which was intended to provide a simple and effective guidance system. This system divided the nose cone of a missile into three compartments, with a pigeon placed in each. Lenses projected an image of distant objects onto a screen in front of each bird. Thus, when the missile was launched from an aircraft within sight of an enemy ship, an image of the ship would appear on the screen. The screen was hinged, such that pecks at the image of the ship would guide the missile toward the ship.[54]

Despite an effective demonstration, the project was abandoned, and eventually more conventional solutions, such as those based on radar, became available. Skinner complained that "our problem was no one would take us seriously."[55] It seemed that few people would trust pigeons to guide a missile, no matter how reliable the system appeared to be.[56]

Early in his career Skinner became interested in "latent speech" and experimented with a device he called the "verbal summator."[57] This device can be thought of as an auditory version of the Rorschach inkblots.[57] When using the device, human participants listened to incomprehensible auditory "garbage" but often read meaning into what they heard. Thus, as with the Rorschach blots, the device was intended to yield overt behavior that projected subconscious thoughts. Skinner's interest in projective testing was brief, but he later used observations with the summator in creating his theory of verbal behavior. The device also led other researchers to invent new tests such as the tautophone test, the auditory apperception test, and the Azzageddi[when defined as?] test.[58]

Challenged by Alfred North Whitehead during a casual discussion while at Harvard to provide an account of a randomly provided piece of verbal behavior,[59] Skinner set about attempting to extend his then-new functional, inductive approach to the complexity of human verbal behavior.[60] Developed over two decades, his work appeared in the book Verbal Behavior. Although Noam Chomsky was highly critical of Verbal Behavior, he conceded that Skinner's "S-R psychology" was worth a review. (Behavior analysts reject the "S-R" characterization: operant conditioning involves the emission of a response which then becomes more or less likely depending upon its consequence–see above.).[61]

Verbal Behavior had an uncharacteristically cool reception, partly as a result of Chomsky's review, partly because of Skinner's failure to address or rebut any of Chomsky's criticisms.[62] Skinner's peers may have been slow to adopt the ideas presented in Verbal Behavior because of the absence of experimental evidence—unlike the empirical density that marked Skinner's experimental work.[63] However, in applied settings there has been a resurgence of interest in Skinner's functional analysis of verbal behavior.[64]

Skinner's views influenced education as well as psychology. Skinner argued that education has two major purposes: (1) to teach repertoires of both verbal and nonverbal behavior; and (2) to interest students in learning. He recommended bringing students’ behavior under appropriate control by providing reinforcement only in the presence of stimuli relevant to the learning task. Because he believed that human behavior can be affected by small consequences, something as simple as "the opportunity to move forward after completing one stage of an activity" can be an effective reinforcer . Skinner was convinced that, to learn, a student must engage in behavior, and not just passively receive information. (Skinner, 1961, p. 389).

Skinner believed that effective teaching must be based on positive reinforcement which is, he argued, more effective at changing and establishing behavior than punishment. He suggested that the main thing people learn from being punished is how to avoid punishment. For example, if a child is forced to practice playing an instrument, the child comes to associate practicing with punishment and thus learns to hate and avoid practicing the instrument. This view had obvious implications for the then widespread practice of rote learning and punitive discipline in education. The use of educational activities as punishment may induce rebellious behavior such as vandalism or absence.[65]

Because teachers are primarily responsible for modifying student behavior, Skinner argued that teachers must learn effective ways of teaching. In The Technology of Teaching, Skinner has a chapter on why teachers fail (pages 93–113): He says that teachers have not been given an in-depth understanding of teaching and learning. Without knowing the science underpinning teaching, teachers fall back on procedures that work poorly or not at all, such as:

Skinner is popularly known mainly for his books Walden Two and Beyond Freedom and Dignity, (for which he made the cover of TIME Magazine).[66] The former describes a fictional "experimental community"[67] in 1940s United States. The productivity and happiness of citizens in this community is far greater than in the outside world because the residents practice scientific social planning and use operant conditioning in raising their children.

Walden Two, like Thoreau's Walden, champions a lifestyle that does not support war, or foster competition and social strife. It encourages a lifestyle of minimal consumption, rich social relationships, personal happiness, satisfying work, and leisure.[68] In 1967, Kat Kinkade and others founded the Twin Oaks Community, using Walden Two as a blueprint. The community still exists and continues to use the Planner-Manager system and other aspects of the community described in Skinner's book, though behavior modification is not a community practice.[69]

In Beyond Freedom and Dignity, Skinner suggests that a technology of behavior could help to make a better society. We would, however, have to accept that an autonomous agent is not the driving force of our actions. Skinner offers alternatives to punishment, and challenges his readers to use science and modern technology to construct a better society.

Skinner's political writings emphasized his hopes that an effective and human science of behavioral control – a technology of human behavior – could help with problems as yet unsolved and often aggravated by advances in technology such as the atomic bomb. Indeed, one of Skinner's goals was to prevent humanity from destroying itself.[70] He saw political activity as the use of aversive or non-aversive means to control a population. Skinner favored the use of positive reinforcement as a means of control, citing Jean-Jacques Rousseau's novel Emile: or, On Education as an example of literature that "did not fear the power of positive reinforcement."[3]

Skinner's book, Walden Two, presents a vision of a decentralized, localized society, which applies a practical, scientific approach and behavioral expertise to deal peacefully with social problems. (For example, his views led him to oppose corporal punishment in schools, and he wrote a letter to the California Senate that helped lead it to a ban on spanking.[71]) Skinner's utopia is both a thought experiment and a rhetorical piece. In Walden Two, Skinner answers the problem that exists in many utopian novels – "What is the Good Life?" The book's answer is a life of friendship, health, art, a healthy balance between work and leisure, a minimum of unpleasantness, and a feeling that one has made worthwhile contributions to a society in which resources are ensured, in part, by minimizing consumption.

If the world is to save any part of its resources for the future, it must reduce not only consumption but the number of consumers.

— B. F. Skinner, Walden Two, p. xi.

Skinner described his novel as "my New Atlantis", in reference to Bacon's utopia.[72]

When Milton's Satan falls from heaven, he ends in hell. And what does he say to reassure himself? 'Here, at least, we shall be free.' And that, I think, is the fate of the old-fashioned liberal. He's going to be free, but he's going to find himself in hell.

One of Skinner's experiments examined the formation of superstition in one of his favorite experimental animals, the pigeon. Skinner placed a series of hungry pigeons in a cage attached to an automatic mechanism that delivered food to the pigeon "at regular intervals with no reference whatsoever to the bird's behavior." He discovered that the pigeons associated the delivery of the food with whatever chance actions they had been performing as it was delivered, and that they subsequently continued to perform these same actions.[73]

One bird was conditioned to turn counter-clockwise about the cage, making two or three turns between reinforcements. Another repeatedly thrust its head into one of the upper corners of the cage. A third developed a 'tossing' response, as if placing its head beneath an invisible bar and lifting it repeatedly. Two birds developed a pendulum motion of the head and body, in which the head was extended forward and swung from right to left with a sharp movement followed by a somewhat slower return.[74][75]

Skinner suggested that the pigeons behaved as if they were influencing the automatic mechanism with their "rituals", and that this experiment shed light on human behavior:

The experiment might be said to demonstrate a sort of superstition. The bird behaves as if there were a causal relation between its behavior and the presentation of food, although such a relation is lacking. There are many analogies in human behavior. Rituals for changing one's fortune at cards are good examples. A few accidental connections between a ritual and favorable consequences suffice to set up and maintain the behavior in spite of many unreinforced instances. The bowler who has released a ball down the alley but continues to behave as if she were controlling it by twisting and turning her arm and shoulder is another case in point. These behaviors have, of course, no real effect upon one's luck or upon a ball half way down an alley, just as in the present case the food would appear as often if the pigeon did nothing—or, more strictly speaking, did something else.[74]

Modern behavioral psychologists have disputed Skinner's "superstition" explanation for the behaviors he recorded. Subsequent research (e.g. Staddon and Simmelhag, 1971), while finding similar behavior, failed to find support for Skinner's "adventitious reinforcement" explanation for it. By looking at the timing of different behaviors within the interval, Staddon and Simmelhag were able to distinguish two classes of behavior: the terminal response, which occurred in anticipation of food, and interim responses, that occurred earlier in the interfood interval and were rarely contiguous with food. Terminal responses seem to reflect classical (as opposed to operant) conditioning, rather than adventitious reinforcement, guided by a process like that observed in 1968 by Brown and Jenkins in their "autoshaping" procedures. The causation of interim activities (such as the schedule-induced polydipsia seen in a similar situation with rats) also cannot be traced to adventitious reinforcement and its details are still obscure (Staddon, 1977).[76]

As understood by Skinner, ascribing dignity to individuals involves giving them credit for their actions. To say "Skinner is brilliant" means that Skinner is an originating force. If Skinner's determinist theory is right, he is merely the focus of his environment. He is not an originating force and he had no choice in saying the things he said or doing the things he did. Skinner's environment and genetics both allowed and compelled him to write his book. Similarly, the environment and genetic potentials of the advocates of freedom and dignity cause them to resist the reality that their own activities are deterministically grounded. J. E. R. Staddon (The New Behaviorism, 2nd Edition, 2014) has argued the compatibilist position; Skinner's determinism is not in any way contradictory to traditional notions of reward and punishment, as he believed.[77]

Noam Chomsky, a prominent critic of Skinner, published a review of Skinner's Verbal Behavior two years after it was published.[78] Chomsky argued that Skinner's attempt to use behaviorism to explain human language amounted to little more than word games. Conditioned responses could not account for a child's ability to create or understand an infinite variety of novel sentences. Chomsky's review has been credited with launching the cognitive revolution in psychology and other disciplines. Skinner, who rarely responded directly to critics, never formally replied to Chomsky's critique. Many years later, Kenneth MacCorquodale's reply was endorsed by Skinner.[79]

Chomsky also reviewed Skinner's Beyond Freedom and Dignity, using the same basic motives as his Verbal Behavior review. Among Chomsky's criticisms were that Skinner's laboratory work could not be extended to humans, that when it was extended to humans it represented 'scientistic' behavior attempting to emulate science but which was not scientific, that Skinner was not a scientist because he rejected the hypothetico-deductive model of theory testing, and that Skinner had no science of behavior.[80]

Cumulative Record: A Selection of Papers, 1959, 1961, 1972 and 1999 as Cumulative Record: Definitive Edition. This book includes a reprint of Skinner's October 1945 Ladies' Home Journal article, "Baby in a Box", Skinner's original, personal account of the much-misrepresented "Baby in a box" device. ISBN0-87411-969-3 (paperback)

^"Within a year I had gone to Miss Graves to tell her that I no longer believed in God. 'I know,' she said, 'I have been through that myself.' But her strategy misfired: I never went through it." B.F. Skinner, pp. 387-413, E.G. Boring and G. Lindzey's A History of Psychology in Autobiography (Vol. 5), New York: Appleton Century-Crofts, 1967.

^Rutherford, A. (2003). "B. F. Skinner and the auditory inkblot: The rise and fall of the verbal summator as a projective technique". History of Psychology. 6 (4): 362–378. doi:10.1037/1093-4510.6.4.362.

Swirski, Peter (2011) "How I Stopped Worrying and Loved Behavioural Engineering or Communal Life, Adaptations, and B.F. Skinner's Walden Two". American Utopia and Social Engineering in Literature, Social Thought, and Political History. New York, Routledge.